1. Field of the Invention
The present invention relates to an apparatus for converting a refrigerant pipe of an air conditioner, and more particularly, to an apparatus for converting a refrigerant pipe of an air conditioner capable of preventing a backflow of a refrigerant even when an air conditioner is stopped and capable of fast re-operating the air conditioner by removing a pressure difference between a refrigerant suction side and a refrigerant discharge side before re-operating the air conditioner.
2. Description of the Conventional Art
Generally, a refrigerating cycle of an air conditioner repeatedly performs a compression process, a condensation process, an expansion process, and an evaporation process. The refrigerating cycle is composed of: a compressor for compressing a refrigerant of a low temperature and a low pressure and thereby converting into a refrigerant of a high temperature and a high pressure; a condenser for condensing a refrigerant of a high temperature and a high pressure into a liquid state; an expander for expanding a condensed refrigerant and thereby converting into a refrigerant of a low temperature and a low pressure; and refrigerant pipes for connecting the compressor, the condenser, and the expander one another.
It is general that one compressor is adopted in an air conditioner. However, recently, plural compressors are adopted in an air conditioner in order to enhance an energy consumption efficiency and to vary a compression function of a compressor according to a load size of a refrigerating cycle.
FIG. 1 is a conceptual view showing a refrigerating cycle of an air conditioner in accordance with the conventional art.
As shown in FIG. 1, the conventional air conditioner comprises: a compressor 1 for compressing a refrigerant; a check valve 2 for preventing a backflow of a refrigerant discharged from the compressor 1; a condenser 30 for condensing a compressed refrigerant into a liquid state; and an evaporator 40 for evaporating a condensed refrigerant.
An electron expansion valve 5 for controlling a flow of a refrigerant according to an operated state of the compressor 11 is installed between the condenser 30 and the evaporator 40. Also, an accumulator 6 for preventing a liquid refrigerant that has not been vaporized from being introduced into the compressor 11 is installed between the evaporator 40 and the compressor 11.
In the refrigerating cycle of the conventional air conditioner, when a refrigerant is compressed as the compressor 11 is operated, the compressed refrigerant is introduced into the condenser 30 via the check valve 2 thus to be condensed. Then, the condensed refrigerant is introduced into the evaporator 40 via the electron expansion valve 5. The refrigerant introduced into the evaporator 40 is vaporized thus to form cool air, and the cool air is blown indoors through a cool air vent of an indoor unit (not shown).
FIG. 2 is a perspective view showing an outdoor unit of the conventional air conditioner having plural compressors, and FIG. 3 is a perspective view showing refrigerant pipes and check valves connected to the plural compressors of the conventional air conditioner.
As shown in FIG. 2, an outdoor unit 10 of the conventional air conditioner includes: plural compressors 11 and 12 for compressing a refrigerant into a high temperature and a high pressure; a condenser 30 for condensing a refrigerant of a high temperature and a high pressure; and an outdoor fan 14 for blowing external air to the condenser 30. An unexplained reference numeral 15 denotes a cover.
A structure of the plural compressors will be explained with reference to FIG. 3. A refrigerant suction pipe 11a and a refrigerant discharge pipe 11b are respectively formed at one side and another side of the first compressor 11. Also, a refrigerant suction pipe 12a and a refrigerant discharge pipe 12b are respectively formed at one side and another side of the second compressor 12.
The refrigerant suction pipes 11a and 12a are connected to each other in parallel, and the refrigerant discharge pipes 11b and 12b are connected to each other in parallel. A check valve 2 for preventing a backflow of a refrigerant is installed at each refrigerant discharge pipe 11b and 12b. 
Unexplained reference numeral 6 denotes an accumulator, 31 denotes a refrigerant circulation pipe of a condenser, and 32 denotes a refrigerant circulation pipe of a suction side of the compressor.
In the conventional air conditioner, the first compressor 11 and the second compressor 12 are respectively operated thereby to suck a refrigerant through the refrigerant suction pipes 11a and 12a and compress. The compressed refrigerant is introduced into the condenser 30 through the refrigerant discharge pipes 11b and 12b via the check valve 2. Then, the refrigerant is condensed by the condenser 30 of FIG. 2, and then passes through the evaporator 40 of FIG. 1 thus to be vaporized and to form cool air. The cool air is blown indoors through a cool air vent of an indoor unit (not shown). The refrigerant vaporized while passing through the evaporator 40 is introduced into the first compressor 11 and the second compressor 12 via the refrigerant circulation pipe 32 and the refrigerant suction pipes 11a and 12a. The above processes are repeated.
While the air conditioner is operated, a user can temporarily stop the operation of the air conditioner in order to perform a defrosting operation to remove frost unnecessarily formed during a cooling operation and then re-operate the air conditioner. In this case, a pressure difference between a refrigerant suction side and a refrigerant discharge side is generated and thereby the air conditioner can not be re-operated within a certain time.
That is, at the time of re-operating the air conditioner after a temporal stopping, the user has to re-operate the air conditioner after removing a pressure difference between a refrigerant suction side (a lower side of the check valve) and a refrigerant discharge side (an upper side of the check valve). According to this, it takes a lot of time to re-operate the air conditioner.
The above phenomenon is generated more severely by the check valve 2 installed at the refrigerant discharge pipes 11b and 12b. Even if the check valve 2 prevents a backflow of a refrigerant while the air conditioner is operated, the check valve causes a pressure difference between the refrigerant suction side and the refrigerant discharge side at the time of re-operating the air conditioner thereby to take a lot of time to re-operate the air conditioner.